Standard liquid-phase cryogenic storage dewars store samples by immersing them in or suspending them just above a pool of liquid nitrogen. Vapour-phase storage systems take a different approach, storing samples in the nitrogen vapour space above the liquid surface. The storage temperature in a well-maintained vapour-phase system is typically between minus 150 and minus 190 degrees Celsius.
There are two primary advantages of vapour-phase storage for IVF use.
The first is sample density. High-capacity vapour-phase units can store thousands of samples in a relatively compact footprint, making them significantly more space-efficient per sample than a bank of standard dewars.
The second is infection control. When samples are stored in direct contact with liquid nitrogen, there is a theoretical risk that microorganisms from one sample could contaminate the shared liquid nitrogen. Vapour-phase storage eliminates direct liquid nitrogen contact, which some clinicians and regulators prefer.
Vapour-phase systems tend to have higher upfront equipment costs than standard dewars and require more sophisticated monitoring. They are most commonly used by larger IVF operations handling high volumes, where the space efficiency and capacity advantages outweigh the additional cost.
Cryolab can advise on whether vapour-phase storage is appropriate for your clinic’s size and growth trajectory. Visit cryolab.co.uk“>Cryolab
